Safety apparatus for presses or other machines



E. DISY. SAFETY APPARATUS FOR PRESSES OR OTHER MACHINES. APPLICATION FILED NOV. 6, 1919- 1,368,788. Patented Feb. 15,1921.

EMILE DISY, OF LYON, FRANCE.

Specification of Letters Patent.

Patented Feb. 15, 1921.

Application filed November 6, 1919. Serial No. 336,081.

To all whom it may concern:

Be it known that I, EMILE DISY, a citizen of the French Republic, of Rue de Montchat, Lyon, France, have invented certain new and useful Improvements in Safety Apparatus for Presses or other Machines, of which the following is a specification.

The apparatus which is the object of this invention makes use of electric currents of the induced or interrupted type known as Faraday or galvanic currents, which act on the contractibility of the muscles, and provokes in the muscles and nerves an induced current to put all persons operating a machine or in the neighbor hood thereof out of the path of accidents by an involuntary reflex movement given automatically by the machine at the moment when an accident would occur.

The drawings hereunto annexed are diagrammatic and show by way of example three forms of the invention applied to a ress.

In the first form of the invention shown in Figure 1, 0. is an electrical dynamo or transformer producing a galvanic current which has the effect of giving a small shock to the motive nerves and setting them in action, so causing an instantaneous contraction of the arm. This generator isin communication by a wire I) with a terminal 0 and spring d terminated by a contact e. The spring (1 is provided with a projection 7 against which the cam 9 comes into contact, which is keyed on to the shaft in of the press or other machine tool to which the invention may be applied. One end of a second insulated conductor 2' is affixed to a conducting plate is by a terminal 3' and the other end to a metal plate 1 of suitable form according to the type of machine it is to be applied to, and which is electrically insulated and placed on the matrix m. The plate is so placed that it is impossible to put ones hand or even a single finger under the plunger of the press without coming into contact with the said plate.

The base a of the machine is connected electrically with the dynamo a either by the ground or by an insulated wire 0.

The working of the arrangement is as follows :When the punch p of the press commences to descend the shaft h which governs the eccentric of the press rotates the cam g which maintains electrical contact with the plate is, and when the cam g has ceased to act on the projection 7' the spring d brings the contact point 6 against the plate k and the electric circuit is closed.

If at this moment which is the dangerous moment, part of the arm or hand touchesthe matrix m it will receive a galvanic shock, which will cause an immediate contraction of the workers arm away from the danger point, if it has been left there too long a time by distraction, inefficiency or any other cause.

The arrangement can be varied accord: ing to the nature of the work to be executed. Thus for example for certain work of precision where the operator is obliged to place the articles one by one on the matrix to insure that they are in the correct position, the plate Z is not arranged on the matrix but the latter is completely insulated by means of a sheet or layer 9 of iebonite or other insulating material. A flexible conductor r is affixed at one end to the contact 0 and at the other to a small metal bracelet s which the operator wears on the wrist of the hand used for placing the articles in position.

The galvanic current is produced when the operator touches the matrix but only at the instant when the punch descends, z. e., at the exact moment when an accident is possible.

Fig. 3 shows a further arrangement applicable for presses in which the operator is obliged to hold a sheet or band of metal which is cut or embossed without interruption. In this case the plate Z is not carried on the matrix but on the guides which carry the punch. It is carried on these guides by spring rods so that it can descend and rise at the same speed as or ata greater speed than the punch p. A cam 9 brings together the two contacts 'v and w to produce a galvanic current to act on the hand of the operator should the latter be under the punch when the latter descends which is the moment an accident is possible.

The current instantly ceases when the plate Z which precedes the punch comes into contact with the sheet and no short circuit is produced as at this moment the cam g has broken the contact between the plates 42 and w.

Other difiierent arrangements but Working on the same principle can be adapted to circular saws and other machine tools where an accident is possible.

What I claim is In combination With a movable element of a machine,ran electrode arranged in such relation to the Work as to cause the hand of the operator to touch said electrode While charged With-galvanic current and thereby cause the same to act on the handiof the operator at a; predetermined stage of movement of said movable element.

J In witness. whereof, I have signed this specification in the presenceof two WIltnesses. V 7' V EMILE DISY Witnesses JEAN GERMAIN,

MARIN .VAoHoN; 

